Whenever you do good indirect deeds for someone. Mainly because some people don’t expect or normally wouldn’t have wanted things to be done in certain ways because it could get them in more shit than they were in the beginning. But sometimes doing things for the good on their behalf is a benefit.
I just wouldn’t mention it to them because it could sometimes create an issue where you may sometimes be faulted or may get into an argument about the morals of having done such thing. So by not mentioning it, it spares you from having to deal with that. I think it also has a net benefit because it doesn’t make you look like you do good things for PR reasons.
The fact that I was born in Soviet Union. Also the fact that the place I was born is now the capital of an Islamic country. Also the fact that I think that Asian cultures in some aspects are better than western ones.